bool Graph::Node::detach(Graph::Node *node)
{
EdgeIterator ei = this->outgoing();
for (; !ei.end(); ei.next())
if (ei.getNode() == node)
break;
if (ei.end()) {
ERROR("no such node attached\n");
return false;
}
delete ei.getEdge();
return true;
}
bool
Graph::Node::reachableBy(Node *node, Node *term)
{
Stack stack;
Node *pos;
const int seq = graph->nextSequence();
stack.push(node);
while (stack.getSize()) {
pos = reinterpret_cast<Node *>(stack.pop().u.p);
if (pos == this)
return true;
if (pos == term)
continue;
for (EdgeIterator ei = pos->outgoing(); !ei.end(); ei.next()) {
if (ei.getType() == Edge::BACK || ei.getType() == Edge::DUMMY)
continue;
if (ei.getNode()->visit(seq))
stack.push(ei.getNode());
}
}
return pos == this;
}
bool
Graph::Node::reachableBy(const Node *node, const Node *term) const
{
std::stack<const Node *> stack;
const Node *pos = NULL;
const int seq = graph->nextSequence();
stack.push(node);
while (!stack.empty()) {
pos = stack.top();
stack.pop();
if (pos == this)
return true;
if (pos == term)
continue;
for (EdgeIterator ei = pos->outgoing(); !ei.end(); ei.next()) {
if (ei.getType() == Edge::BACK || ei.getType() == Edge::DUMMY)
continue;
if (ei.getNode()->visit(seq))
stack.push(ei.getNode());
}
}
return pos == this;
}
// @dist is indexed by Node::tag, returns -1 if no path found
int
Graph::findLightestPathWeight(Node *a, Node *b, const std::vector<int> &weight)
{
std::vector<int> path(weight.size(), std::numeric_limits<int>::max());
std::list<Node *> nodeList;
const int seq = nextSequence();
path[a->tag] = 0;
for (Node *c = a; c && c != b;) {
const int p = path[c->tag] + weight[c->tag];
for (EdgeIterator ei = c->outgoing(); !ei.end(); ei.next()) {
Node *t = ei.getNode();
if (t->getSequence() < seq) {
if (path[t->tag] == std::numeric_limits<int>::max())
nodeList.push_front(t);
if (p < path[t->tag])
path[t->tag] = p;
}
}
c->visit(seq);
Node *next = NULL;
for (std::list<Node *>::iterator n = nodeList.begin();
n != nodeList.end(); ++n) {
if (!next || path[(*n)->tag] < path[next->tag])
next = *n;
if ((*n) == c) {
// erase visited
n = nodeList.erase(n);
--n;
}
}
c = next;
}
if (path[b->tag] == std::numeric_limits<int>::max())
return -1;
return path[b->tag];
}
